Anogenital Human Papillomaviruses (HPVs) are the most common sexually transmitted pathogen and the primary cause of cervical cancer. The goal of this combined R21/R33 grant application is to screen for small molecules that can inhibit HPV infection, to identify related compounds with improved effectiveness, and to test the effectiveness of the most promising compound in a preclinical model for HPV infection. In the R21 Phase of this grant application, we will carry out a high throughput screen to identify candidate HPV-specific microbicides. We will validate and prioritize these primary hits through a series of secondary screens using established infectivity assays that define specific targets steps in the infection process. In the R33 phase of this grant proposal we will pursue the identification of second generation small molecules using a virtual screening tool to screen a database of 4.5 million small molecules for ones with similar structures to those identified in the R21-phase screen. The ten best candidate microbicides will be screened in vivo for reproductive toxicology in the mouse and from this the top candidate microbicide will be chosen for studies in a nonhuman primate model for anogenital HPV infection, based upon monitoring infection by Rhesus papillomavirus (RhPV1) in the reproductive tract of female Rhesus macaques. The feasibility of the studies proposed in this grant application rest upon our recently having developed a powerful and facile new technique for high yield production of infectious papillomaviruses. This breakthrough provides sufficient amounts of papillomavirus to allow one to screen for microbicides as well as to develop the RhPV1 -based nonhuman primate model for anogenital papillomavirus infections.